Device for drying the closing flaps of letter envelopes, bags, etc.



c. H. JAGER June 21, 1938.

DEVICE FOR DRYING THE CLOSING FLAPS OF LETTER ENVELOPES, BAGS, ETC

Filed Dec. 6, 1955 l atented June 21, 1938 PATENT. OFFICE .nnvron ron. name 'rnr. CLOSING FLAPS or LETTER nuvanoras, mes, arc.

Carl Hugo Jam, Wuppertal-Elberfeld,

Germany Applicationbecember 6, 1935,Serial No. 53,274

. In Germany December 6, 1934 5 Claims.

The gumming and drying of the closing flaps to one another in a staggered fashion that, normally, they would'stickto one another. To avoid the danger of sticking, holders are arranged in between the single-blanks that keep the gummed flaps apart.

on the other hand, the blank has already been creased with the closing flap remaining to be gummed and dried, drying chains are employed generally. The envelopes with the closing flap either still uncreased, or creased, fall into open links of the transporting chain which are closed as the chain moves along, care being taken that the gumming of the closing flap cannot get stuck anywhere. adapted for use in connection with machines for small and determined sizes. If, however, envelopes of various sizes are to be dried on a chain and the range between the smallest and the largest size envelope produced is considerable, it is recommended to effect the drying by placing the envelopes on drying belt conveyors.

With the current systems of drying on belt conveyors, the creased envelopes are arranged in a staggered fashion on the conveyor or band. To avoid any shifting out of place and to insure the perfect gluing of p the lateral and bottom flaps of the envelopes, a pressure must be exerted upon the latter. To do so, the use of bands running on the lateral edges of the envelopes is generally resorted to. This, however, has the disadvantage that no glue must be applied where the bands are passing as these would get stuck at Such chains are particularly the conveying band, this arrangement a of the glue being applied to the closing flaps down to their very corners. In view of the fact, however, that with high-speed creasing and gluing machines the envelopes are generally fed into 5 the machine'with the bottom flap forward, the envelope-with the mechanism described-must besubjected to a change in direction as now the closing flap will have to go in n st.

Such a change of direction ofiers considerable 10 difliculties whensusing thin paper and working at great speeds, and to avoid them, the present invention provides for the envelope being fed into the drying mechanism without any'chan'ge of direction. The envelopes being placed in be- 15 tween partitions, or bridges, fastened to endless chains, are transported to the drying conveyor, the partitions, or bridges, pressing the envelopes against the conveyor belt until they are com-v pletely dry, and without exerting any pressure 20 upon the gummed closing flap. The glued parts of the lateral and bottom flaps are pressed against one another by the partitions whereby perfectgluing is insured, while the gummed parts of the closing flaps are held apart by the partitions; avoiding thereby any danger of their sticking to one another. a With reference to the drawing, Fig. 1 is 8. diagrammatic side elevation of approximately normalscale showing the introduction of the envelopes into the chain, Fig. 2 is a side elevation of the mechanism on a smaller scale, and Fig. 3 is a top view thereof.

The method of operatiomis as follows: A pair of conveying rollers I, 2 (Figs. 1 to 3) pushes the envelopes arriving with their closing flap freshLv gummed from the gumming station (not shown here) between the partitions 3 of a transport chain 4 onto a conveyor band 5 in such a way that the envelopes come'to rest between the 40 conveyor band and the partitions 3 of the chain 4. The envelopes are introduced to the chain at a point where its course is curved, and the partitions 3 are pointing at this time in about the direction from which the envelopes are brought onto the conveyor. In Figs. 1 and 2 the chain is shown to move up vertically from below, it being conducted along horizontally as soon as the blanks have been introduced. Afterthe envelopes have been introduced, the partitions 3 assume a position vertical to the envelope, thus urging the closing flap upwardly and at the same time holding the envelope in position with relation to the conveyor belt which has the same speed as the chain. 56

The pair of rollers I, 2, however, is not capable of pushing smaller size envelopes far enough into the chain. For this reason,.a suction roller 6 has been provided within the chain possessing. approximately the same speed as the envelope drawn toward the interior, and attracting the envelope and pushing the same against the stops 1 in order to give the envelopes a predetermined position in relation to the chain bridges 3. A rotating member having shoulders or stops 1 on its periphery has approximately the same speed as the conveyor belt, or the chain, to avoid any danger of shifting of the envelopes that have been introduced. The stops are ready always to position each new envelope brought forward, in such a way, that they are introduced registerlike on the drying track. In order tocope with envelopes of different size the stops are designed to be adjustable in a forward or backward direction.

As the bridges are located below the closing flap as soon as the envelope has been introduced, the closing flap in moving-on is lifted upward by the bridges. Thereby, a'wedge-shaped spaceis created between the suction roller 6 and the envelope introduced last which serves for the reception of the next following envelope. The chain 4 on which the bridges 3 are mounted is guided by the rails 8 and in that way forced into a predetermined position in relation to the conveyor belt. The rails are equipped withguiding slides 9 fastened to one another by the bell crank levers l0 and connecting rod II in such a way that the rails 8 may be lifted and lowered by turning the lever l2. Owing to this adjustability of the rails to a higher or lower position, flat as well as baggy envelopes may be passed through the drying mechanism without any danger of their being pressed by the bridges. The chain tightening rollers l3 are adjusted thereby simultaneously.

After the closing flap has dried, the chain 4 is led away from the belt in such a way that the envelopes come to lie open once more. Rollers, or balls, serve the purpose of holding the envelopes against the conveying belt to prevent the envelopes shifting after the bridges 3 have been eliminated. Pawls l4 serve to bring the envelopes in alignment once more, whereupon the discs l5 provided with recesses and rlmning alongside the belts 5 at an increased speed, draw oneenvelope away from the belt with each revolution. It will be understood that in this operation the forward edge of the envelope runs against a stop 16 of the reversing plate l1. Thereupon, the closing flap is folded over and the finished envelopes are collected in a basket I8.

This novel drying mechanism makes it possible to introduce completely creased envelopes with freshly gummed closing flaps into a drying mechanism in such a way that the envelopes may be gummed up to their very edges. At the. same time, there is no need of any change of direction being effected and, consequently, with the employment of this mechanism, a very high speed may be obtained.

For the purpose of drying envelopes of various sizes, there exists no longer any necessity of adjustments being made on the bands, regulating the stops 1 being all there is required.

I claim: I 1. A machine for drying the flaps of envelopes comprising a conveyor, means for depositing envelopes having wet gummed flaps on the conveyor,

a second conveyor having plates adapted to receive wet gummed flaps of the envelopes and hold them out of contact one with another, guide means positioned laterally of the first named conveyor to keep the envelopes in lateral position, means for folding over the flaps upon the body of the envelope after the said flaps have become dry and having means for removing the said guide means to permit irregular envelopes to be carried'by the said conveyor.

2. A machine for'drying the flaps of envelopes comprising a conveyor, means for depositing envelopes having wet gummed flaps upon the said conveyor, means for holding the sealed edges of the envelopes together while holding the gummed flaps apart as the envelopes are conveyed during drying, means for holding the flaps and the bodies of the envelopes fiat after the drying, means for thereafter folding over the dried gummed flaps upon the bodies of the envelopes and means for automatically maintaining uniform pressure on the edges of the envelopes regardless of changing thicknesses of the envelopes. I

3. A machine for drying the wet gummed flaps of envelopes comprising a conveyor for the envelopes while undergoing drying, means for depositing envelopes having wet gummed flaps upon the conveyor, a second conveyor having plates thereon and movable through a portion of its travel vertically and laterally, first to position the plates in place to receive the flaps of the envelopes as the envelopes are deposited on the first named conveyor and thereafter to move the flaps angularly with respect to the bodies of the envelopes. 1

4. The structure of claim 1 and means for automatically maintaining uniform pressure on the edges of the envelopes regardless of changing thicknesses of the envelopes.

5. In a machine for drying the closing flaps of envelopes, bags and the like, a conveyor for moving the envelopes while drying the flaps, means for depositing envelopes having wet gummed flaps in spaced relation upon the conveyor, a second conveyor movable about and adjacent the first mentioned conveyor, means on 'said second conveyor engageable with said flaps for holding them out of contact with one another by changing the angular position of the flaps with respect to the bodies of the envelopes as the envelopes are moved along and movable at substantially the samespeed as the first mentioned conveyor, 'and' stop means for positioning the envelopes at a predetermined distance apart on the conveyor, said stop means comprising a rotatable roller having shoulders on its periphery, moving in the same direction as the envelopes deposited on the first mentioned conveyor.

CARL HUGO JAGER. 

